From ReefPedia

Crabs:Beneficial or Harmful?

(The Answer is Both)

While some will swear up and down that crabs have no place in reef tanks, others feel that certain crabs- especially some types of hermit crabs- are beneficial detritivores.

In truth, all crabs are opportunisitic feeders. You can expect them to take advantage of any wounded or dying animal in your tank, they have also been known to attack snails for the shell.

Detritivores

Crabs commonly considered detritivores include the common hermit crabs, as well as sally lightfoot crabs and decorator crabs.

Often, these crabs are included as a vital part of a reef's "clean-up crew."

Algaevores

Still other crabs are used to rid reef aquaria of unwanted algae. Major players for this function include the Emerald Crab and the Sally Lightfoot Crab. While these crabs will certainly eat some of the tank's algae, do not expect them to only eat the things you don't want them to. Both crabs have been reported to attack invertebrates, and Sally Lightfoot crabs in particular are known to attack fish- especially when the crab gets larger.

Is it "safe?"

One popular rule of thumb is that if a crab is hairy, it needs to go. In most cases, these crabs will actively attack either fish, other invertebrates, or both.

Common Reef Aquarium Crabs:

The types of crabs typically found in reef aquaria include:

Hermit Crabs

• Scarlet Hermit Crab
• Zebra Hermit Crab
• Halloween Hermit Crab
• Blue-Leg Hermit Crab
• Red-Leg Hermit Crab

Other Crabs:

• Decorator Crab
• Sally Lightfoot Crab
• Teddy Bear Crab
• Emerald Crab Mithrax sp.
• Arrow Crab

Articles in category "Crabs"

There are 10 articles in this category.

A Arrow Crab B Blue-Leg Hermit Crab D Decorator Crab

E Emerald Crab H Halloween Hermit Crab R Red-Leg Hermit Crab S Sally Lightfoot Crab

S cont. Scarlet Hermit Crab T Teddy Bear Crab Z Zebra Hermit Crab